In a radio communications system, in order for a user equipment (User Equipment, UE for short) to measure downlink channel state information (Channel State Information, CSI for short), a base station needs to send a certain reference signal to the UE in a coverage area for the purpose of downlink channel measurement. For example, in a Third Generation Partnership Project (the 3rd Generation Partnership Project, 3GPP for short) Long Term Evolution (Long Term Evolution, LTE for short) Release 11 (Release 11) protocol, in order for the user equipment to measure downlink channel state information (Channel State Information, CSI for short), the base station further needs to configure one or more channel state information interference measurement (Channel State Information—Interference Measurement, CSI-IM for short) resources for the UE, and the UE measures interference on the CSI-IM resources and calculates the CSI according to the measured interference.
In the prior art, to obtain higher user throughput, a coordinated multi-point transmission and reception (Coordinated Multiple Point transmission and reception, CoMP for short) technology may be applied in the communications system. The coordinated multi-point transmission and reception technology refers to that multiple access points provide data services for one or more users simultaneously. When coverage of a macro base station in the coordinated multi-point transmission and reception technology fully includes coverage of a micro base station, the user equipment (User Equipment, UE for short) can be served by both the macro base station and the micro base station in a specific region of a cell covered by the micro base station. When the UE is located in the cell covered by the micro base station and served by the micro base station, and the UE needs to measure the CSI presumed to exist when the UE is served by the macro base station, the UE needs to measure interference including micro base station interference according to the CSI-IM resources, and calculate the CSI according to measured interference result information.
However, on the CSI-IM resources, a signal received by the UE from the micro base station may be a data signal, and consequently, the interference measured by the UE according to the CSI-IM resources is not accurate.